Sunday, January 20, 2008

Earth Hour is an interesting idea cooked up by the citizens of Sydney Australia and begun on March 31st, 2007. From the Toronto Star,

More than 2 million residents pulled the plug and the city went dark. Energy usage dropped by 10.2 per cent across the business district, more than double what organizers were aiming for, representing a reduction of 25 tonnes of carbon dioxide – the equivalent of taking 48,613 cars off the road for an hour.

Earth Hour is a great idea to show people the impact of climate change. It also shows people about the impact of light pollution. Light pollution is a major problem for astronomers but it also now being recognized as having other environmental effects. They've even got a word for it, scotobiology. The basic idea from a recent article, here, is that:

Plants and animals are programmed to function in a certain pattern of daylight and darkness. Alter it and unhealthy things happen. It applies equally to organisms that are active at night and those, including humans, whose bodies require regular periods with the lights out.

Unfortunately the organizers don't seem to have taken into consideration that most of North America will be on Daylight Savings Time during Earth Hour and people will not get the full effect of the night sky. Here's my hope that they schedule it an hour later (or two weeks earlier) in 2009.